The present invention relates to a lever fitting type connector capable of fitting a male connector to a female connector by rotating a lever mounted to the male connector.
Recently, a lever fitting type connector for reducing a fitting operation force by means of a lever is employed upon fitting both male and female connectors having terminals of multi poles to each other (for example, see Patent Document 1).
This kind of lever fitting type connector is shown in FIG. 18. A lever fitting type connector 100 shown in FIG. 18 includes a male connector 121, a lever 122 of which a center portion is rotatably mounted to a boss portion 127 of a side surface 125 of a male connector 121, and a female connector 123 having a fitting space into which the male connector 121 is inserted.
The lever 122 includes a pair of side plates 128 overlapping with the both side surfaces 125 of the male connector 121 and an operation portion 129 connecting the other end portions of the pair of side plates 128 to each other. Additionally, each side plate 128 is provided with a hole for allowing the boss portion 127 to be positioned to the center portion; a fulcrum protrusion 130 provided on the side of one end portion thereof so as to serve as a fulcrum upon rotating the lever; and a temporary retaining portion 138 provided at the lower end portion on the side of the other end portion thereof. The temporary retaining portion 138 is used to prevent the lever 122 from rotating to the female connector 123 by being positioned to a position more away from the female connector 123 than a temporary fixing convex portion 137 protruding from the side surface of the male connector 121 at an initial fitting step.
The female connector 123 includes a female-type connector housing 132 having a fitting space. An inner wall forming the fitting space of the connector housing 132 is provided with a fulcrum protrusion guiding groove 134 extending from the upper end portion of the inner wall toward the inside of the fitting space; a fulcrum protrusion receiving groove 135 connected to the fulcrum protrusion guiding groove 134 and extending in a direction intersecting the fulcrum protrusion guiding groove 134; and a plate-shape release plate portion 139.
The fulcrum protrusion receiving groove 135 is a groove for positioning the fulcrum protrusion 130 thereto upon rotating the lever 122 so as to allow the fulcrum protrusion 130 to serve as a fulcrum of the lever 122.
As the male connector 121 moves close to the female connector 123, the release plate portion 139 advances to the inside of the temporary retaining portion 138 so as to allow the temporary retaining portion 138 to be bent outward, thereby allowing the temporary retaining portion 138 to pass over to the temporary fixing convex portion 137 on the side of the female connector 123.
In the lever fitting type connector 100, the fulcrum protrusion 130 is positioned to the inside of the fulcrum protrusion receiving groove 135 after passing through the fulcrum protrusion guiding groove 134. When the operation portion 129 is pressed toward the female connector 123 to thereby rotate the lever 122 in this state, the fulcrum protrusion 130 serves as a fulcrum, the hole for positioning the boss portion 127 serves as an action point, and then the male connector 121 is pressed into the fitting space, thereby fitting the male connector 121 to the female connector 123. Additionally, when the fulcrum protrusion 130 is positioned to the inside of the fulcrum protrusion receiving groove 135, the release plate portion 139 advances to the inside of the temporary retaining portion 138 so as to allow the temporary retaining portion 138 to pass over to the temporary fixing convex portion 137 on the side of the female connector 123, thereby releasing the unrotatable state of the lever 122.
[Patent Document 1] JP-A-2000-91026
The above-described lever fitting type connector 100 has the following problems to be solved. That is, in the related lever fitting type connector 100, a problem arises in that an idle rotation of the lever 122 occurs in a case where the unrotatable state of the lever 122 is released before the fulcrum protrusion 130 is positioned to the inside of the fulcrum protrusion receiving groove 135.
The inventors of the invention have investigated the reason and have found out that a timing at which the unrotatable state of the lever 122 is released becomes different in accordance with a method of applying a force to the operation portion 129 since an angle of a taper portion 139a formed on the upper end portion of the release plate portion 139 is gentle, and hence a lever operation stroke becomes long when the temporary retaining portion 138 passes over the taper portion 139a. 
Additionally, a locking force (a temporary lock holding force) of the temporary retaining portion 138 applied to the temporary fixing convex portion 137 in order to maintain the unrotatable state of the lever 122 is determined by an amount in which the temporary retaining portion 138 overlaps with the taper portion 139a. The locking force becomes zero at a time point when the temporary retaining portion 138 completely passes over the taper portion 139a. That is, the unrotatable state of the lever 122 is released.